Manufacture of ordnance and projectiles.



PatentedI Oct. 23, [900! J. A. P0TT`l ER. MANUFAGTUBE 0F ORDNANGE ANDPBJECTILES.

(Apliction mea Apr. 15. 189s.)

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No. 66c,22|. Patented out. 23,19%.- A. POTTER.

MANUFACTURE 0F DRDNANCE AND PROJECTILESV.

(Application le Apr. 15. 189B.)

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v'UM'TED STATES f PATENT OFFICE.

JOHN A. POTTER, OE CLEVELAND, OHIO.

MANUFACTVURE OF ORDNANCE AND PROJECTILES.

S1"ECIIiI-GATIONY forming part of Letters Patent N o. 660,221, datedOctober 23, 1900.

Applcationviiled April 15, 1898. Serial No. 677,660. (No model.)

To all whom zit may concern:

Be it known that I, JOHN A. POTTER, of Cleveland, in the county ofCuyahoga and State of Ohio, have invented a new and useful Improvementinthe Manufacture of Ordnance and Projectiles, of which the following is afull, clear, and exact description, reference being had to theaccompanying drawings, forming part of this specification, in which-Figure 1 is a sectional elevation of one form of press constructed inaccordance with my invention. Fig. 2 is an enlarged partial seotion ofanother form, showing the plungers in depressed position. Fig. 3 is ahorizontal section on the line III IlI'of Fig. 2; and Figs. 4, 5, and 6are partial sectional elevations showing other forms of the press.

My invention relates to the manufactureof ordnance and projectiles, andisdesigned to' provide an improved method therefor, Whereby sucharticles may be cast without substantial piping or segregation in theinterior of the casting.

To that end it consists in subjecting the molten metal to an endpressure until the outer shell is solidified, keeping the end portionhot and then subjecting the central end portion to a further pressure,thus preventing the iiuid interior portion from piping and from internalstrains and segregation.

In the drawings, referring to the form of Figs. 1, 2, and 3, 2represents a mold which is built up of interiitting steel plates, whichare preferably water-cooled by pipes or channels 3 and which are boltedtogether by pins or bolts 4, extending through slots cut in the edges ofthe sections. These slots are so ar'- ranged that they register inalternate plates, the arrangement of the pins or bolts being clearlyshown in Figs. 2 and 3. l show' the mold as resting upon a base 5,carried upon the plunger of a hydraulic ram 6,'carried centrally in thefoundation of the machine and arranged to lift the base-plate from theroll-I ers 7 7, upon which the plate and mold are carried into positionin the press. 8 8 are the side standards of the press, which form guidesfor a vertically-reciprocating cross-head 9, secured to the plunger 10of a hydraulic cylinder 11. This plunger 10 -is hollow and cut out inits lower portion, so as to receive ya steel ring 17, adapted to containa plug 18 of refractory material,this plug being of about the samediameter as the ram or rod 13. I provide at the sides of the cylinder 11small lifting-cylinders 19, the rods of whose pistons are connected tothe cross-head 9 .and serve to lift the same after the operation iscompleted. Fluid-pressure is admitted to the interior of the hollow ram10 through a tubular `extension 20, extending through the top of itscylinder and secured to the ram, the fluid passing through a jointedpipe 21. The smaller ram 12 is lifted by a rod 22, extending upwardlythrough the tubular extension to a-piston 23 in an upperlifting-cylinder 24.

The operation is as follows: The mold, which has been suitably linedwith a refractory material, as shown, being filled with molten steeliiuid pressure is admitted to the larger cylinder 11, thus forcing downthe cross-head and pressure block and `subjecting the molten steel to aheavy hydraulic pressure. The inner ram 12 moves down with the plunger10,

vremaining at the same point in the outer plunger during this operation.the outer shell of metal next to the mold has As soon as chilled so thatthe metal cannot be further compressed in its outer portionsduid-pressure is admitted within the hollow plunger 10, thus forcingdown the inner ram 13. This ram acting upon the refractory plug 18forces this plug through the ring 17 into the central portion of thestill liquid metal and subjects the same to a heavy pressure.- In orderto prevent the plunger from entering and becoming embedded in thesolidifying steel after it has forced down the refractory plug, itis-lifted sufficiently to allow the granular material inthe cavity oflthe pressure-block to feed down into the opening through the botloo tomof the block, and the ram 13 then being forced down again a'cts throughthis intermediate material upon the interior partiallycooled body of themetal. This operation is repeated as often as desirable. The ring 17reduces the area upon which the smaller ram operates, and as the top ofthe ingot chills the ring becomes secured in place and fastened in andsustained by the castings and 1o sustains the intensified pressure uponthe small ram and concentrates its power at the desired point. The gaseswill pass up into the cavity of the pressure-block and thence outthrough the filling-openings. The refrac- 15 tory plug being ofnon-conducting material tends to keep the central portion of the metalhot, and thus allows the compressive action of the inner plunger to beexerted thereon. Ihe central piping and segregation of thei 2o castingis thus prevented and an exceedingly y strong homogeneous metal isobtained throughout it. I may obtain this successive` pressure firstupon the entire body of the` metal and then upon its inner hotterportion in many other Ways. Thus in Fig. l I show a single ram 25,having secured to its lower end a pressure-block l26, the lower part ofwhich is reduced in` diameter and is surrounded by a series of rings orcollars. The

3o lowermost ring 27 is provided with a centrali curved block 28, i ofrefractory material, against the central partof which the endl: of thepressure block abuts. Above this ring is an inner collar 29, surroundingthe reduced portion of the block, and surrounding this collar are tworings 30, the lower of which. is composed of steel, while the upper iscomposed of zinc or some easily-fusible metal.` The upper face of thezinc ring is in the samef 4o plane as the top of the collar, andcovering them both is an annular plate 3l of" steel, lz above which isan inner zinc ring 32 and outer zinc ring 33, the ring 33 being of lessthick-` ness than the ring 32. When the ram is forced l down to bringthe pressure upon" the molten i steel in the mold in this form, theblock of l; refractory material will keep the central part a of thesteel hot, and theheat being conducted .l from the metal upwardly:through the rings 5o and collars will gradually soften and `melt thezinc ring 30. The outer shell of the castl ing having cooled during thesoftening of this ring the whole `pressure of the ram is brought b uponthe block and its collar 29, which bearing upon the refractory blockwill drive it;

down into the hotter metal and compress it. j

As the portions next to the outer shell con- ,1 geal, thus preventingfurther downwardI` movement of the collar, theheatvwill be cony ooducted to the zinc rings 32 33, and these rings i will soften and melt,allowing the reduced part of the block to move down within the l1 collar29 and act upon the central portion of l the molten metal. I am thusenabled to aui tomatically concentrate the pressure which l is firstbrought upon the entire body of molten metal upon its intermediate'andcentral por'- tions successively during the congealing of the casting,thus obtaining a solid compact metal.

In the form of Fig. 5 the rings 34 and 35, surrounding the reducedportion of the pressure bl`ocl above the collars 36 and 37, are of steeland are made in two or more parts, so that after the ram is depressed tobring the pressure upon the molten metal the plunger may be lifted and aportion of these rings removed, so as to allow the block andintermediate collar nt'o press upon Athe inner hotter portion of themetal, and when these are cooled it may be again raised and the innerrings removed, after which the plunger'is again de-` pressed, an'd theblock sliding down within the collars acts upon the central part only ofthe cooling metal.

In the form of Fig. 6 I employ in place of the steel pressure-block ablock 38 of wood, such a lignum-vitae, which may be provided in itslower face with a block of refractory materialand may be providedwithencircling bands or hoops sunk in annular recesses to preventcrushing of the block. When this block is forced down into the steel,its portions around the refractory material will char and gradually burnaway, so that the pressure will be applied to the central part of themolten metal, thus concentrating thepressure upon the hotter parts "ofthe metal, as in the previous forms.

I may carry out my process with ya plain solid steelblock of shape shownin Fig. 6, this block being secured to the lower end iof the plungerandfitting into the upper end of the mold-cavity by feeding in `granularmaterial, such as hot sand, and forcing this material down upon thecooling metal. As the outer shell cools `more material is fed in andwill be forced down in' the `central hotter portions, soas toconcentrate the pressure thereon, as before- The advantages of myinvention will be apparent to those skilled in `the art. Thecompressiveforce is exerted throughout the entire coolingA and solidifying of thesteel, thus obviating the piping and internal strains heretofore causedby the contraction of the interior fluid metal after the `outer shellhas solidied. The rapidvcooling of the article is hastened by the greatpressure and consequent close contact of the metal with the mold, and agreater pressure maybe exerted upon lthe interior of the articlethanfcould be "carriedmby the mold were it not for the solidified shell`surrounding the interior hot metal. The inner `part of the article iskept hot by the refractory plug or material, and the conipressive actionmay thus be prolonged upon `this part. The gases expelled from the steel`by the great pressure brought thereon will pass into the refractorylining and thence thro ughthe jointsbetweenthe mold-sections.

The invention is applicable also to the mak- IOO IIO

ing of ingots, shafts, and other castings, and I intend to cover thesame when used upon any casting apparatus.

Many changes may be made in the form and arrangement of the press and inthe means for applying pressure to the inner hotter portion of the metalas the outer parts chill and harden Without departing from my invention,

since What I claim isl. The method of making castings, consisting insubjecting molten metal in the mold to endwise pressure over a'majorportion of its area, keeping the central end portion hot, and thencompressing this central portion alone by further localized pressureafter the har- JOHN A. POTTER.

Witnesses:

J. C. JONES, Jr., F. H. HART.

